# US 11,114,299 B2 · Techniques for reducing tip to tip shorting and critical dimension variation during nanoscale patterning > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,114,299 B2 - Document ID: US11114299B2 - Status: Granted - Kind: B2 - Application number: 16/569,944 - Filed: 2019-09-13 - Published: 2021-01-07 - Granted: 2021-09-07 - Earliest claimed: 2019-07-05 - Assignees: Applied Materials, Inc. - Applicants: APPLIED Materials, Inc. - Inventors: Qintao Zhang; Kyu-Ha Shim; Rajesh Prasad - Web page: https://patentgrep.com/patent/US11114299B2 ## CPC - H10P 50/695: {characterised by the process involved to create the mask, e.g. lift-off masks or sidewalls or to modify the mask} - H10P 76/2043: {using an anti-reflective coating} - H10D 30/024: {of fin field-effect transistors [FinFET]} - H10P 30/40: into insulating materials - H10P 50/287: {by chemical means} - H10P 50/73: {using masks for insulating materials} - H10P 95/08: {Planarisation of organic insulating materials} - H10W 20/089: {using processes for implementing desired shapes or dispositions of the openings, e.g. double patterning} - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 ## Abstract A method of forming surface features in a hardmask layer, including etching a first surface feature into the hardmask layer, the first surface feature having a first critical dimension, performing an ion implantation process on the first surface feature to make the first surface feature resistant to subsequent etching processes, etching a second surface feature into the hardmask layer adjacent the first surface feature, wherein the first critical dimension is preserved. ## Claims ### Claim 1 A method of forming surface features in a hardmask layer, comprising: etching a first surface feature into a top surface of the hardmask layer, the first surface feature having a first critical dimension; performing an ion implantation process on the first surface feature, wherein an ion beam formed of an ionized dopant species is directed at the first surface feature and implants the ionized dopant species into the first surface feature to make the first surface feature resistant to subsequent etching processes; depositing a planarization layer on the hardmask layer, the planarization layer filling the first surface feature; and etching a second surface feature into the top surface of the hardmask layer distant from the first surface feature along the top surface of the hardmask layer; and performing an etching process to remove the planarization layer from the hardmask layer and from within the first surface feature, wherein the first surface feature is resistant to the etching process and the first critical dimension is preserved. ### Claim 2 (depends on 1) The method of claim 1, wherein the first surface feature and the second surface feature are trenches. ### Claim 3 (depends on 1) The method of claim 1, wherein the first critical dimension is a width of the first surface feature. ### Claim 4 (depends on 1) The method of claim 1, wherein the planarization layer is a second planarization layer and wherein etching the first surface feature into the hardmask layer comprises: performing a photolithography process using a first photoresist layer to etch a trench into a first planarization layer and first bottom antireflective coating (BARC) layer disposed on the hardmask layer; and performing an ion etching process wherein an ion beam formed of reactive plasma ions is directed into the trench to extend the trench into the hardmask layer. ### Claim 5 (depends on 4) The method of claim 4, further comprising removing the first photoresist layer, the first planarization layer, and the first BARC layer from the hardmask layer. ### Claim 6 (depends on 1) The method of claim 1, wherein the dopant species is selected from one of carbon, boron, difluoroboron, germanium, and silicon to make the first surface feature resistant to subsequent etching processes performed on the hardmask layer. ### Claim 7 (depends on 1) The method of claim 1, further comprising performing an ion implantation process on the second surface feature to make the second surface feature resistant to subsequent etching processes. ### Claim 8 (depends on 7) The method of claim 7, wherein the second surface feature has a second critical dimension, further comprising etching a third surface feature into the hardmask layer adjacent the second surface feature, wherein the first critical dimension and the second critical dimension are preserved. ### Claim 9 (depends on 1) The method of claim 1, further comprising performing an etching process on the hardmask layer wherein the first and second surface features are extended entirely through the hardmask layer and into an underlying semiconductor layer. ### Claim 10 A method of forming surface features in a hardmask layer, comprising: providing a layer stack including the hardmask layer, a first bottom antireflective coating (BARC) layer disposed on the hardmask layer, a first planarization layer disposed on the BARC layer, and a first photoresist layer disposed on the first planarization layer; performing a first photolithography process to etch a first trench patterned by the first photoresist layer into the first planarization layer and the first BARC layer; performing a first ion etching process wherein an ion beam formed of reactive plasma ions is directed into the first trench to extend the first trench into the hardmask layer, the first trench having a first critical dimension; performing an ion implantation process on the first trench to make the first trench resistant to subsequent etching processes; removing the first photoresist layer, the first planarization layer, and the first BARC layer from the hardmask layer; applying a second BARC layer, a second planarization layer, and a second photoresist layer a atop the hardmask layer; performing a second photolithography process to etch a second trench patterned by the second photoresist layer into the second planarization layer and the second BARC layer; and performing a second ion etching process wherein an ion beam formed of reactive plasma ions is directed into the second trench to extend the second trench into the hardmask layer, wherein the first critical dimension is preserved. ### Claim 11 A method of forming surface features in a hardmask layer, comprising: etching a first surface feature into the hardmask layer, the first surface feature having a first critical dimension and having lateral sidewalls extending in a first direction and longitudinal sidewalls extending in a second direction perpendicular to the first direction; etching a second surface feature into the hardmask layer, the second surface feature spaced apart from the first surface feature a first distance in the first direction, the second surface feature having a second critical dimension and having lateral sidewalls extending in the first direction and longitudinal sidewalls extending in the second direction; performing an ion implantation process on the lateral sidewalls of the first and second surface features to make the lateral sidewalls resistant to subsequent etching processes; and performing an etching process on the first and second surface features, wherein the longitudinal sidewalls of the first and second surface features are etched to shorten a spacing between the first and second surface features from the first distance to a second distance, and wherein the lateral sidewalls are unaffected by the etching process and the first and second critical dimensions are maintained. ### Claim 12 (depends on 11) The method of claim 11, wherein the first surface feature and the second surface feature are trenches. ### Claim 13 (depends on 11) The method of claim 11, wherein the first critical dimension and the second critical dimension are lateral widths of the first and second surface features, respectively. ### Claim 14 (depends on 11) The method of claim 11, wherein etching the first surface feature into the hardmask layer comprises: performing a photolithography process using a first photoresist layer to etch a trench into a first planarization layer and first bottom antireflective coating (BARC) layer disposed on the hardmask layer; and performing an ion etching process wherein an ion beam formed of reactive plasma ions is directed into the trench to extend the trench into the hardmask layer. ### Claim 15 (depends on 14) The method of claim 14, further comprising removing the first photoresist layer, the first planarization layer, and the first BARC layer from the hardmask layer. ### Claim 16 (depends on 15) The method of claim 15, further comprising applying a second BARC layer, a second planarization layer, and a second photoresist layer a atop the hardmask layer. ### Claim 17 (depends on 11) The method of claim 11, wherein performing the ion implantation process on the lateral sidewalls of the first and second surface features comprises directing an ion beam formed of an ionized dopant species at the lateral sidewalls, the dopant species selected from one of carbon, boron, difluoroboron, germanium, and silicon to make the lateral sidewalls resistant to subsequent etching processes performed on the hardmask layer. ### Claim 18 (depends on 11) The method of claim 11, further comprising performing an etching process on the hardmask layer wherein the first and second surface features are extended entirely through the hardmask layer and into an underlying semiconductor layer. ### Claim 19 (depends on 11) The method of claim 11, wherein the second distance is in a range of 2 nanometers to 100 nanometers.